Smith the watershed approach
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Transcript of Smith the watershed approach
Identifying Nutrient Sources, Flowpaths, and Priority Practices
Douglas R. Smith, USDA-ARS
Lake Erie and Harmful Algal Blooms
2011 Central Lake Erie Basin Microcystis-containing bloom
DRP (kg P/ha)
TP (kg P/ha)
Maumee 0.273 1.12Sandusky 0.311 1.41Honey Cr. 0.369 1.29Rock Cr. 0.250 1.38
Nutrient Budgets, Sources and Pathways
2010 Field and Watershed Mass Balance
Field 4 – 8.6 ac
Soybean
16.7 lb P/acFertilizer
32.6 lb P/ac Harvest
Field 1 – 5.4 ac
Corn
20.8 lb P/ac Harvest
Field 3 – 9.9 ac
Soybean16.7 lb P/acFertilizer
32.6 lb P/ac Harvest
78.4 lb P/ac Poultry Litter
Field 2 – 6.7 acCorn
78.4 lb P/ac Poultry Litter
20.8 lb P/ac Harvest
Ditch Site 1736 ac
Ditch Site 24,780 ac
Ditch Site 310,600 ac
Stream Site 447,600 ac 0.52 lb P/ac
Lake Erie
Maumee River4,064,000 ac
30.2 in. rain
1 lb P205 = 0.44 lb P
100 lb DAP/ac = 46 lb P205/ac = 20.1 lb P/ac
2011 Field and Watershed Mass Balance
Field 4 – 8.6 ac
Wheat
18.5 lb P/acFertilizer
17.6 lb P/ac Harvest
Field 1 – 5.4 ac
Soybean
16.8 lb P/ac Harvest
Field 3 – 9.9 ac
Wheat18.5 lb P/acFertilizer
17.6 lb P/ac Harvest
NoFertilizer
Field 2 – 6.7 acSoybean
NoFertilizer
17.1 lb P/ac Harvest
Ditch Site 1736 ac
Ditch Site 24,780 ac
Ditch Site 310,600 ac
Stream Site 447,600 ac 0.68 lb P/ac
Lake Erie
Maumee River4,064,000 ac
36.5 in. rain
1 lb P205 = 0.44 lb P
100 lb DAP/ac = 46 lb P205/ac = 20.1 lb P/ac
Legacy Phosphorus in Fields Crop roots utilize only a small proportion of the soil volume leading to poor nutrient capture
A large proportion of applied P is immobilized in soils by inorganic and organic processes
Critical soil test P levels vary widely from site to site leading to insurance‐based applications
Soil sampling/analysis is crude, has high uncertainties leading to potential misinterpretation
Contributions from organic P and subsoil P are largely ignored
Courtesy: Paul Withers
According to the Tri-state Fertility Guide, no P fertilizer application recommended beyond 50 ppm P
J F M A M J J A S O N D
Volu
met
ric D
epth
(mm
)
0
2 0
4 0
6 0
8 0
1 0 0
1 2 0
1 4 0
1 6 0
1 8 0P re c ip > P E TP E T2 0 0 5 -2 0 1 0 P re c ip
• 25% of cropland in US and Canada could not be farmed without tile drainage (Skaggs et al., 1994):• soils with the greatest inherent production potential
• Tile Drainage (Fausey et al., 1987):• provides trafficable conditions for field operations• promotes root development by preventing exposure of plants to excess water
Drainage and Fertilizer Spreading Season
Hydrologic Year 2008-2011 Maumee River Soluble Phosphorus Loading
Day of Hydrologic Year (Day 1 = October 1)
0 100 200 300
Tota
l Pho
spho
rus
Load
(kg)
0
200000
400000
600000
800000
HY08 Soluble PHY09 Soluble PHY10 Soluble PHY11 Soluble P
84.6%
61.9%
44.3%
81.1%
Fertilizer Spreading “Season”
St. Joseph River Watershed
!\
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!\!\!\!\!\!\
Matson D
itch
Swartz Ditch
W Smith D
itch
Cedar Creek
Dibbling Ditc
h
Leins Ditch
Hof
feld
er D
itch
Cedar Creek
Matson Ditch
AD
AS2AS1
F34
CME
CLG
BME
BLG
AME
ALG
MI
IN
OH
MI
INOH
MI
Ontario
Tile Drainage
Direct Drainage
Pot-Hole
! LowPoint
¯
0 50 100 150 200 250
Miles0 5 10 15 20 25
Miles
0 0.5 1 1.5 2 2.5Miles
Nutrient losses were higher from watersheds with more:‒ Direct Drainage‒ Pothole Drainage
Influence of Drainage Class on Nutrient Losses
2008.0 2009.0 2010.0 2011.0
Tota
l P in
Sur
face
Run
off (
kg P
/ha)
0.0
0.5
1.0
1.5
2.0
2.5
3.0
Field 1 Field 2 Field 3 Field 4 Maumee
Total P in Surface Runoff from Fields and Maumee River
2008 2009 2010 2011
Tota
l P in
Tile
(kg/
ha)
0.0
0.5
1.0
1.5
2.0
2.5
Field 1 Tile Field 2 Tile Field 3 Tile Field 4 Tile Maumee
Total P in Tile Flow from Fields and Maumee River
Soil Test Phosphorus 0-2" (mg/kg)0 100 200 300 400 500 600
DR
P co
ncen
trat
ion
(mg/
L)
0.0
0.5
1.0
1.5
2.0
DRP concentration rangesite median
Relationship between soil test phosphorus and dissolved phosphorus concentration in tile discharge (UBWC and Upper Wabash watersheds)
What’s Wrong with the Current System?
Courtesy: K. King
Surface and Tile Discharge – St. Joe
Precip = 0.73 inchSurface Q = 0.03 inchTile Q = 0.16 inch
Precip = 1.56 inchSurface Q = 1.27 inchTile Q = 0.22 inch
3/2 /12 6:00 3/2 /12 6:00 3/3 /12 6:00 3/3/12 6:00
flow
rate
(lps
)
0
10
20
30
40pr
ecip
itatio
n (m
m)
0
1
2
3
4
5
surface d ischargetile d ischargeprecip ita tion
0
2
4
6
8
10
12
14
16
prec
ipita
tion
(mm
)
0
2
4
6
8
10
12
14
surface runofftile dischargeprecipitation
5/8/12 5/9/12 5/10/12
Dis
char
ge (L
ps)
0
2
4
6
8
10
12
14
160
2
4
6
8
10
12
14
3 /2 /1 2 6 :0 0 3 /2 /1 2 6 :0 0 3 /3 /1 2 6 :0 0 3 /3 /1 2 6 :0 0
flow
rate
(lps
)
0
1 0
2 0
3 0
4 0
prec
ipita
tion
(mm
)
0
1
2
3
4
5
s u r fa c e d is c h a rg et ile d is c h a rg ep re c ip ita t io n
Two different tile: same soil, different responses
0.5 inch rainfall 1.25 inches rainfall
EOF Results – (OH – UW; K. King)
Watershed Results—2005‐2010 UBWC
Courtesy: K. King
40% of annual total phosphorus load at EOF from tile discharge (Enright and Madramootoo, 2004)
25% of TP and 50% of soluble P leaving watershed originated in tile drainage (Culleyand Bolton, 1983)
Soluble P Total P2005 0.317 0.2342006 0.346 0.3002007 0.313 0.2642008 0.756 0.7592009 0.591 0.4852010 0.669 0.630
AVG 0.499 0.445
Fraction of annual watershed loading
originating from tile
Watershed Loss (kg)
0 20 40 60 80 100 120 140 160
Ti
le L
osse
s (k
g)
0
20
40
60
80
100
120
140
160
Total PSoluble P
y = 0.457x+0.219R2 = 0.86
y=0.342x+0.173R2=0.72
LEGACY PHOSPHORUS
Sediment source tracking indicated about
50% of sediment was from field sources and 50% from stream bank.
Roughly ½ of sediment (and by proxy P) is from stream bank or stream
bed
Conservation Practices
Ohio P Task Force International Joint Commission
Goals to reduce P loading to Lake Erie by ~40%
Expectations for Water Quality Improvement
Grassed waterwaysContour filter strips
Conservation cover
Practices for Managing Runoff & Water Quality
Sediment detention basins
Alternative Surface Drainage
Tile Riser Blind Inlet
Novel Practices: Re-Saturated Buffer
In-Channel Phosphorus Retention
Mark Tomer, ARSJoe Magner, Univ. Minn.
Entrained wetlands
Constructed wetlands
Two-stage ditch
Stream restoration/reconnection
Pete Kleinman, ARS
Decrease P loading to achieve WQ goalsNo single source of P No single pathway of PNo silver bulletWill require an “all of the above” approach to meet WQ goalsHow do we plan for landscape scale conservation???
Conclusions
?Thank You!
Total and Soluble Phosphorus Loading
Dave Baker and Pete Richards, Heidelberg University
“Peak” adoption of no‐till
P Loading to Lake Erie
Municipal Direct15%
Municipal Indirect5%
Industry PS Direct0%
Industry PS Indirect0%
Trib Monitored52%
Trib not Monitored18%
Atmospheric Deposition
6%
Lake Huron4%
P Loading to Lake Erie (1994-2008)
Average Total Phosphorus Loading to Lake Erie is 10,875 ton/year
Dolan and Chapra, 2012
SP Load by Management
No-Till Rotation Till Conv Till/8yr Rot
SP L
oad
(g h
a-1)
0
100
200
300
400
500
TP Load by Management
No-Till Rotation Till Conv Till/8yr Rot
TP L
oad
(g h
a-1)
0
200
400
600
800
1000
1200
1400
Informational Survey of Farmers and CCAs
Manage or advise > 35,000 ha
Asked about N, K and P deficiency
N and K deficiency common
P deficiency only when‒ Sidewall compaction‒Cool/wet post‐emerge‒Herbicide damage
Hydrologic Year 2008-2011 Maumee River Total Phosphorus Loading
Day of Hydrologic Year (Day 1 = October 1)
0 100 200 300
Tota
l Pho
spho
rus
Load
(kg)
0
1000000
2000000
3000000
4000000
HY08 Total PHY09 Total PHY10 Total PHY11 Total P
86.7%
49.5%
87.4%
45.8%
Fertilizer Spreading “Season”